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Earthworks are the embankments and cuttings that allow a railway to maintain a certain line, level and grade through the landscape. Earth embankments consist of an engineered bank of earth that carries the railway above the natural ground. A cutting is used to carry the railway through ground with a natural level above the line of the railway. Modern (post 1960s) earthworks are carefully engineered to perform well. However, many railways run on earthworks that were constructed over 100 years ago without the use of mechanised plant. The quality of construction of older earthworks was often poor compared with present-day engineering practice. Ageing of the earthwork structures, and the greater demands of heavier and faster trains and climatic change, means that earthworks suffer ultimate and serviceability failures that can present operational difficulties. Older earthworks that fail or do not perform well require maintenance and repair, and sometimes complete replacement. This chapter explores the main engineering considerations for modern earthworks, and the challenges associated with older earthworks including their modes of failure and upgrade and repair.

The study aims to analyse the stability of embankments over the improved ground with stone column (SC) and pervious concrete column (PCC) inclusions using limit equilibrium method. The short-term stability of PCC-supported embankment system is rarely addressed. Therefore, the factor of safety (FOS) of column-supported embankment system is calculated using individual column and equivalent area models.

The stability analysis of column-supported embankment system is conducted using PLAXIS LE 2D. The various geometrical and shear strength parameters influencing the FOS of these embankment systems such as diameter of columns, spacing between columns, embankment height, friction angle of column material, undrained cohesion of weak ground and cohesion of PCC are considered.

The critical failure envelope of PCC-supported embankment system is observed to be of toe failure, whereas the failure envelope of stone column-supported embankment system is generally of deep-seated nature.

It is found that for PCC embankment system, FOS and failure envelope are not influenced by the geometrical/shear strength parameters other than height of embankment. However, for stone column-supported embankment system, FOS and failure envelope are dependent on all the shear strength and geometrical parameters considered in this study.

This paper aims to investigate the behaviour of geosynthetic reinforced deep cement mixed (DCM) column-supported embankments constructed over soft soils.

Coupled consolidation analyses based on the finite element method are carried out assuming that the soil and DCM columns are fully saturated porous mediums. In the first part of the paper, a case study of an embankment constructed over a very soft soil deposit in Finland is presented. Two- and three-dimensional finite element models for the case study are developed including isolated and attached DCM columns beneath the embankment to capture the arching mechanism between DCM columns. The model simulations were carried out considering the actual staged construction procedure adopted in the field. Finite element predictions show good agreement with field data and confirm that the load transfer is mainly between attached columns beneath the embankment. Next, the significance of geosynthetic reinforcement on the load transfer mechanism is investigated. Finally, the influence of permeability of columns and soft soil on the performance of geosynthetic reinforcement column-supported embankments is studied.

Results demonstrate that the excess pore pressure dissipation rate is fast in DCM column-improved ground compared to the same case without any columns, although the same permeability is assigned to both DCM columns and surrounding soft soil. When DCM column permeability exceeds soil permeability, excess pore pressure dissipation rate shows a remarkable increase compared to that observed when the DCM column permeability is less than or equal to the permeability of surrounding soft soil. [ ]

This paper investigates the contribution of permeability and geosynthetic layer on the vertical load transfer mechanism of the embankment and modelling issues related to application of the embankment load and the properties of the cement-improved columns.

The decision of livelihood based on the embankment characters is essentially multivariate. Making an effort to do the bivariate modelling may eliminate the useful socio-economic information in the interdependent and simultaneous adaptation choices (Dorfman, 1996). Hence, the more appropriate method is multiple-choice decisions to livelihood adoption based on the embankment category. The purpose of this study is to find out whether the inhabitants of Sundarban really consider embankment as their “lifeline”, what they think about its sustainability and what the outer world thinks about the embankment.

To analyse this study, the multinomial logit (MNL) model has been used. This model gives a platform to study the influence of the factors on livelihood choice decisions. In this MNL model, the livelihood decisions are categorized based on their primary livelihood status at the survey. Thus, the choice of livelihood among individuals is explained in terms of the livelihood and the household characteristics.

This result can possibly explain the fact that increasing population or man power and increasing annual income and protection from embankment failure may reduce the need to choose any other form of economy apart from the indigenous one, as the society is dominated by farmers who own very small plots of land and face consequences like crop failure every year because of natural calamities. A unit increase in annual income would result in a 0.53% decrease in the probability of choosing labourer as occupation and 0.57% decrease in the probability of choosing fishing/“meen” collection as occupation.

The district is vast enough, and it is difficult to study all the blocks. Initially, nine blocks were identified as affected blocks from various literature reviews. Those blocks are Sagar, Patharpratima, Kultali, Gosaba, Kakdwip, Canning I, Canning II, Namkhana and Basanti. Pilot surveys were done to all those nine blocks identified above. After such a long and rigorous procedure, blocks were verified from available secondary data. Villages from vulnerable and less vulnerable parts of the later mentioned blocks are picked up as purposive sample, and household surveys are done on the basis of random sampling.

If the year of schooling is enhanced, then the tertiary sector gets benefited, but the indigenous society of Sundarban cannot depend on such a sector as the scope for development is very limited. Consequently, policies aiming at promoting adaptation to challenged livelihood need to emphasize the crucial role of providing basic needs for better production techniques; and more investment in this sector will surely enable villagers to adapt cultivation following age-old tradition.

The study uses the MNL model to investigate the factors guiding household choices of different occupational adaptation methods, and cultivation is found to be the automatic choice for the inhabitants of Sundarban. Cultivation is impossible without embankment. Thus, the embankment in Sundarban is considered, as “lifeline” is established. So it can be said that livelihood in this region depends on the stability of embankment. This age-old structure is susceptible to vulnerability because of its unscientific construction and improper maintenance. The main objective of this study is to find out whether the inhabitants of Sundarban really consider embankment as their “lifeline”, what they think about its sustainability and what the outer world thinks about the embankment.

Buried pipelines under various soil embankment heights are cost-effective alternatives to transporting liquid products. This paper aims to assist pipeline architects and professionals in selecting the most cost-effective buried reinforced concrete pipelines under deep embankment soil with minor structural reinforcement while meeting shear stress requirements, safety and reliability constraints.

It is unfeasible to experimentally assess pipeline efficiency with high soil fill depth. Thus, to fill this gap, this research uses a dependable finite element analysis (FEA) to conduct a parametric study and carry out such an issue. This research considered reinforced concrete pipes with diameters of 25, 50, 75, 100, 125 and 150 cm at depths of 5, 10, 15 and 20 m.

According to this research, the proposed best pipeline diameter-to-thickness (D/T) proportions for soil embankment heights 5, 10, 15 and 20 m are 8.75, 4.8, 3.5 and 3.1, correspondingly. The cost-effective reinforced concrete (RC) pipeline thickness dramatically rises if the soil embankment reaches 20 m, indicating that the soil embankment depth highly influences it. Most of the analyzed reinforced concrete pipelines had a maximum deflection value of less than 1 cm, telling that the FEA accurately identified the pipeline width, needed flexural steel reinforcement, and concrete crack width while avoiding significant distortion.

The cost-effective thickness for the analyzed structured concrete pipes was calculated by considering the lowest required value of steel reinforcement. An algorithm was developed based on the parametric scientific findings to predict the ideal pipeline D/T ratio. A construction case study was also shown to assist architects and professionals in determining the best reinforced concrete pipeline geometry for a specific soil embankment height.

Slope stability analysis is essential for ensuring the safe design of road embankments. While various conventional methods, such as the finite element approach, are used to determine the safety factor of road embankments, there is ongoing interest in exploring the potential of machine learning techniques for this purpose.

Within the study context, the outcomes of the ensemble machine learning models will be compared and benchmarked against the conventional techniques used to predict this parameter.

Generally, the study results have shown that the proposed machine learning models provide rapid and accurate estimates of the safety factor of road embankments and are, therefore, promising alternatives to traditional methods.

Although machine learning algorithms hold promise for rapidly and accurately estimating the safety factor of road embankments, few studies have systematically compared their performance with traditional methods. To address this gap, this study introduces a novel approach using advanced ensemble machine learning techniques for efficient and precise estimation of the road embankment safety factor. Besides, the study comprehensively assesses the performance of these ensemble techniques, in contrast with established methods such as the finite element approach and empirical models, demonstrating their potential as robust and reliable alternatives in the realm of slope stability assessment.

Distributed temperature sensing (DTS) can identify locations and factors of seepage in embankments. Inspired by the classical transient hot-wire method (THW), the focus of this paper is to investigate the feasibility and propose a calibrated method of seepage velocity monitoring using the optical fiber DTS.

According to the definition and the measurement of thermal conductivity, the nominal thermal conductivity, which comprehensively reflects the influence of heat transfer and seepage factors, is proposed and the corresponding solution is also derived. Then, a flume testing platform of an embankment seepage monitoring system composed of the optical fiber heat-up subsystem, the seepage controlling subsystem and the optical fiber DTS subsystem is designed and built. Meanwhile, the data processing and assistant analysis subsystem (DPAAS) is also developed to effectively acquire the experimental data of concerned locations and obtain the corresponding nominal thermal conductivity under various seepage conditions. Based on these setups, a series of laboratory flume experiments are carried out under controlled velocities and heating powers.

The plots of recorded temperature rise versus natural logarithm of time allow the calculation of nominal thermal conductivities, and then the seepage velocity monitoring model particular to the experimental setup is successfully established with satisfactory precision.

Considering the complexity of water flow in embankments, a seepage flume that matches the natural system, allowing for larger experimental model scales, various water temperatures, various engineering materials and a wider range of seepage velocities, should be investigated in future.

The combined THW and DTS method provides promising potential in real-time seepage monitoring of embankment dams with the help of the developed DPAAS.

In this work, we performed a flume testing of seepage velocity monitoring platform using optical fiber distributed-temperature sensing for embankments based on the transient hot-wire method. Through the testing of data, the seepage velocity monitoring model particular to the experimental setup was established. The results presented here are very encouraging and demonstrate that the DTS system can be used to monitor the temperature and the seepage factors in field applications.

Development of effective disaster risk reduction (DRR) strategies for communities at risk of being affected by natural disasters is considered essential, especially in the wake of devastating disaster events reported worldwide. As part of a wider research study investigating community perspectives on existing and potential strategies for enhancing resilience to natural disasters, community perspectives on infrastructure and structural protection requirements were investigated. The paper aims to discuss these issues.

Patuakhali region in South-Western Bangladesh is a region significantly at risk of multiple natural hazards. In order to engage local communities and obtain their perspectives, focus group discussions were held with local community leaders and policy makers of at-risk communities in Patuakhali region, South-Western Bangladesh.

Infrastructure and structural protection requirements highlighted included multi-purpose cyclone shelters, permanent embankments and improved transport infrastructure. Much of the discussions of focus group interviews were focused on cyclone shelters and embankments, suggesting their critical importance in reducing disaster risk and also dependence of coastal communities on those two measures.

The research design adopted sought to answer the research questions raised and also to inform local policy makers on community perspectives. Local policy makers involved in DRR initiatives in the region were informed of community perspectives and requirements, thus contributing to community engagement in implementing DRR activities.

People from chronic flood-affected areas in the Sundarban islands understand that individual efforts are not sufficient to deal with the floods of increasing magnitude caused by tidal waves in coastal areas and take proactive measures to minimise the impact of floods before turning to the government for support. Their perception of disaster risk influences them to engage in collective activities and develop strategies to mitigate flood disasters. However, many villagers do not participate in collective disaster management activities. The purpose of this paper is to explore the factors of homogeneity that motivate people to work together to reduce the impact of natural hazards.

Qualitative research has been conducted in Sibpur and Gobordhanpur villages of Indian Sundarban islands. Participant observation and in-depth interview have been applied to explore the collective activities of disaster reduction. Affected, non-affected villagers, representatives of the local government and government administrative officers have been interviewed to understand the disaster management efforts of the government and local people.

The research has found that drivers of homogeneity and leadership are important for collective activities in disaster management. Threat of disasters, potential loss of livelihood and damages of properties, emotional attachment with the village and ties with extended family members influence villagers to engage in collective activity. Collective activities of villagers help to address the local needs of disaster reduction to the government in a better way.

The study has revealed that strong leadership is required in effective collective activities to manage disaster in the Indian Sundarban islands.

Elasto‐plastic models based on critical state formulations have been successful in describing many of the most important features of the mechanical behaviour of soils. This review paper deals with the applications of this class of models to the numerical analysis of geotechnical problems. After a brief overview of the development of the models, the basic critical state formulation is presented together with the main modifications which have actually been used in computational applications. The problems associated with the numerical implementation of this type of models are then discussed. Finally, a summary of reported computational applications and some specific examples of analyses of geotechnical problems using critical state models are presented.